| 摘要 |
PROBLEM TO BE SOLVED: To easily and surely judge via an antenna the whole of the state of a large number of articles having electronic tags attached thereto. SOLUTION: This electronic tag device includes an inner cylinder 30 having a electronic tag 20 built in, an outer cylinder 10 enabling the inner cylinder 30 to move longitudinally therein, and a reader for data recorded on the electronic tag 20; the cross-sectional shape of the inner cylinder 30 on a plane perpendicular to the direction of movement within the outer cylinder 10 is approximately the same as the cross-sectional shape of the outer cylinder 10 on a similar plane. A weight may be provided inside the inner cylinder 30. Alternatively, the inner cylinder may be filled with a liquid of a rather great specific gravity to float the electronic tag 20. When a plurality of outer cylinders 10 are arranged side-by-side, the electronic tags 20 can be easily arranged in similar positions. |
